The relevance of this article is due to the necessity of development cognitive activity of schoolchildren at a higher level. Its main goal is to identify the main ways of effective development logical thinking of junior students. Problems of determining the specifics of development this phenomenon in Russian and Bulgarian elementary systems and in identifying the main directions of development children’s cognitive activity in the process of using logical operations are considered in it. This article consists of introduction, the main part and inference presented by conclusions. The article consists of introduction, the main part and conclusion. The main part of the article involves two problematic issues: definition of specifics of development of this phenomenon in Russian and Bulgarian systems of primary education and identification the main directions of development of children’s mental activity in the process of using logical operations. The answer to the first problematic issue is based on the study of Russian-Bulgarian literature on mastering initial forms of cognitive activity; on the development of the ability to reflex; to create structural and functional models and to master basic logical operations. The answer to the second problematic issue involves the implementation of the following areas: block structuring of educational material; using logical methods of forms and means; forming the ability of independent systematization of educational material. The author offers four series of tasks for each direction. The first series of tasks is related to the grouping educational material on the basis of integration and differentiation. The second series of tasks was used at the lessons of various types on the basis of two signs (the degree of innovation and the source of knowledge). The third series of tasks is aimed at drawing up structural and logical schemes and formulating conceptual trunks. The fourth series of tasks involves finding local control points. In the inference the author comes to the conclusion that the implementation of these areas will systematize educational material at different levels of cognition of primary schoolchildren. The article is intended for teachers and teachers of higher education.

Keywords: logical thinking, logical operations, junior schoolchildren, direction.